Abstract

An experiment was performed with the aim to determine the expansionvelocity of the corona that is formed around a wire exploded in vacuum. The corona expansionvelocity was found for Al and W wires as the wire current density was increased to . It was estimated by the time at which current started flowing through auxiliary electrodes separated from the wire axis by a certain distance. The measurements were performed with preliminary heated and unheated wires. It has been demonstrated that for unheated wires the expansionvelocity of the plasma corona is determined by the expansionvelocity of the desorbed gas and approximately equals , , and at a generator charge voltage of 10, 20, and 30 kV, respectively. For preliminary heated tungstenwires the metal vapor expansionvelocity was , , and at a charge voltage of 10, 20, and 30 kV, respectively.

Received 19 October 2009Accepted 27 January 2010Published online 26 March 2010

Article outline:I. INTRODUCTIONII. THE EXPERIMENTAL SETUP AND PROCEDUREIII. EXPERIMENTAL RESULTSIV. DISCUSSIONA. Simulation of the explosion of a preheated tungstenwireB. Formation of the corona around an exploded unheated wireC. Plasma density at the onset of current through the auxiliary electrodesV. CONCLUSION